Processes for winding and doffing bobbins



Aug. 2, 1966 D. F. G. MANSFIELD ET AL 3,253,410

PROCESSES FOR WINDING AND DOFFING BOBBINS Original Filed Sept. 14, 1962 4 Sheets-Sheet l Aug. 2, 1966 MANsFlELD ET AL 3,263,410

PROCESSES FOR WINDING AND DOFFING BOBBINS Onginal Filed Sept. 14, 1962 4 Sheets-Sheet 2 F/GZA.

I nvenlor s A tlorneys Aug. 2, 1966 D. F. G. MANSFIELD ET AL 3,263,410

PROCESSES FOR WINDING AND DOFFING BOBBINS Original Filed Sept. 14, 1962 4 Sheets-Sheet 5 I Inventors I A Horn e ys PROCESSES FOR WINDING AND DOFFING BOBBINS DTlgiflal Filed 5613i. 14, 1962 4 Sheets-Sheet 4,

Attorneys United States Patent 1 Claim. c1. s7-1ss This is a division of application Serial No. 223,710, filed September 14, 1962, now abandoned.

The present invention concern improvements in or relating to processes for winding and doffing bobbins.

It is well known that during the winding of bobbins of yarn for use, for instance, as warping yarn, the first turns of yarn wound on to the bobbin are wound separately from the main body of yarn in order to provide an available tail of yarn for use in connecting the last length of yarn to be Withdrawn from the bobbin with the leading end of yarn of another bobbin.

In order that the yarn at this tail end shall run freely when the time comes for it to be withdrawn, it is important that the tail shall be comprised of properlyspaced helical turns on the bobbin surface that Will not jam on withdrawal; and it is the main object of the invention to provide a process for winding and dOfllng bobbins on a ring spindle apparatus that will ensure that a tail is properly formed and secured in place at one end of the bobbin.

According to the invention, yarn is wound on a bobbin on a ring spindle apparatus, and the bobbin is dotted, by a process comprising the steps of Winding the initial lengths of yarn on a waste spool spaced heightwise below the bobbin, Winding spaced turns of yarn in the form of a helix on the lower end-portion of said bobbin, said turns connecting the yarn on said waste spool with the main build of yarn on the bobbin, completing the winding of the main build of yarn, and doffing the bobbin by lifting it upwardly of the spindle of the said ring spindle apparatus so that yarn in the lower of said helical turns is automatically trapped in a slot for-med in a radial projection from the surface of the bobbin or formed between the projection and the surface of the bobbin itself, the line of direction of said slot towards its open end being such as to intersect the line of direction of yarn in said helical turns.

The invention employs a bobb-in with yarn wound in a package therein and having a transfer tail comprising spaced helical turns on its lower end-portion, said helical turns being secured by the lowermost one being trapped in a slot formed in a radial projection from the surface of the bobbin, or formed between the project-ion and the surface of the bobbin itself.

The invention will now be described, for the purposes of illustration only, with reference to the accompanying drawings and in connection with the winding and dofling of bobbins of synthetic yarn, such as nylon, immediately after the drawing (stretching) operation.

In the drawings,

FIGURE 1 is a diagrammatic representation of apparatus for drawing (stretching);

FIGURE 2, FIGURE 2A, and FIGURE 2B show the manner in which projections can be formed at the base of a plastic sleeve;

FIGURE 3 shows how projections can be made by the use of plastic strips at the base of a bobbin;

FIGURE 4 shows how a projection can be made in a rubber band at the base of a bobbin;

, 3,263,410 Patented August 2, 1966 "ice FIGURE 5 is a diagrammatic representation, partly in section, of a ring spindle at the start of winding according to the invention;

FIGURE 6 is a diagrammatic representation, partly in section, of the lower portion of the apparatus of FIG- URE 5, during a subsequent part of the winding;

FIGURE 7 is a diagrammatic representation, partly in section, of the apparatus of FIGURE 6, at the completion of winding and at the start of dofling; and

FIGURE 8 shows how the transfer tail is trapped at the base of the bobbin of FIGURE 7 on completion of dotfing.

The drawing (stretching) apparatus depicted in FIG- URE 1 comprises a holder 1 for cake 3 of undrawn yarn, yarn guide 5, tension bars 7, and traverse guide 9 for traversing the undrawn yarn across feed roll 11. Nip roll 13, acting in conjunction with feed roll 11, ensures that the undrawn yarn is forwarded positively. Snubbing pin 15 is positioned intermediate the feed roll 11 and draw roll 17, around the latter of which and separator roll 19, the yarn is wound with a number of wraps. Thence, the drawn yarn proceeds via balloon guide 21 to be wound up by the ring spindle apparatus comprising rotatable spindle 23, with waste spool 25 at the base thereof, whorl 27, around which driving belt 29 is passed, and ring 31 held in holder 33 and around which traveller 35 rotates. The yarn is Wound in package 37 on a bobbin (not shown) aifixed to spindle 23.

It is explained that the initial lengths of yarn produced at the start of winding will be either undrawn or incompletely drawn, and these are the lengths which are wound on the waste spool. Such winding is effected by a lowering of the traveller ring, either individually or as one of a number of such rings held by a ring rail, to below its ordinary operating traverse range; and such ring is slowly raised to operating position, once the drawing operation has started to run smoothly, thus producing the series of spaced helical turns connecting the yarn on the Waste spool with the yarn in the main build. The yarn is then wound into the main build by traversing it in the required manner along the main middle portion of the bobbin; and when the required amount of yarn has been so wound, the ring is lowered to the level of the waste spool, the end of yarn is severed and winding ceases. The spindle is then braked to bring it to rest for the dotting of the bobbin which is carried out by lifting the bobbin vertically for a short distance, either by hand or with the assistance of a defining tool, until it can be removed from the spindle.

Although only one radial projection has been referred to above, it is in fact preferred to use at least two of them, to ensure that the helix of yarn is readily trapped; and the actual form to be taken by a projection, apart from the basic requirements that it shall project slightly from the cylindrical periphery of the lower end-portion of the bobbin and that the line of direction of the slot towards its open end shall intersect the line of direction of yarn in the helical turns, will depend on the type of bobbin in use. For the most part, producers bobbins employed in the Winding of synthetic yarns such as nylon are cylindrical tubes without flanges; and they may be composed of plastic or cardboard sleeves fitting closely on a metal core, or of a metal tube itself. It is a relatively simple matter to form or to cut projections in the sleeves; but in the case of all-metal bobbins it is necessary to fit a sleeve or band over the lower end-portion of the bobbin, this sleeve or band having the projection or projections formed in it.

In connection with FIGURES 2-4, and considering firstly bobbins composed of a plastic sleeve 39 and metal core 41, it is possible to make the sleeve with the projection or projections 43 integral therewith and extending below the base thereof from its periphery. Such projections, as shown in FIGURES 2 and 2A, having a slot formed along the line of the periphery and half the width of the projection in length, can be raised slightly to stand out from the surface of the bobbin (FIGURE 2) or they can be bent right over upwardly (FIGURE 2A), the latter arrangement providing a more positive means for engagement with the helical coils 45. Alternatively, as shown in FIGURE 2B, V-shaped flaps 43 can be punched out of the base of the sleeve 39, with the apex of the V pointing upwardly and sideways so as to provide a slot int-o which the helical coil or coils will be drawn on dotting the bobbin. In yet another alternative, as shown in FIGURE 3, which can also be employed with cardboard sleeves, a small strip 47 of plastic material can be wedged between the sleeve 39 and the plastic cone-shaped fitting at the base of the metal core 41 so as to project below the end periphery of the sleeve, and this strip, having a slot cut through half its width along the line of the periphery, is then bent right over upwardly to form a projection 43 in the same way as described above for the integral projections.

For the all-metal bobbins, as well as for those consisting of a sleeve fitted on a metal core, a plastic sleeve can be pressed over the base of the bobbin, this sleeve having diagonal slots cut in one or two places around its upper periphery. It is possible, as shown in FIGURE 4, to use a stretched rubber band 49 or an expansible metal clip around the lower end-portion of the bobbin 41 instead of a plastic sleeve pressed over its base, the rubber bandor metal clip having notches cut in its upper periphery in the same way as the plastic sleeve, to form projections 43 which stand out sideways from the band or clip.

The operation of the winding and doffing of a bobbin according to the invention is described with reference to FIGURES 5-8.

At the start of winding, as shown in FIGURE 5, the machine is threaded-up by passing the yarn round the feed and draw rolls (see FIGURE 1) through the guide 21 and traveller 35, and then the yarn is anchored by being wound around the spindle blade 23. The bobbin 41 is then loaded on to the spindle.

The machine is then started. The ring 31, which may be controlled by an automatic bunch winder, remains stationary long enough for the undrawn and off-standard yarn produced during startup to be wound on to the waste spool 25. The ring 31 is then raised and whilst rising it winds a spiral of yarn 45 over the waste spool 25 and the lower portion of the bobbin 41, as shown in FIGURE 6. At this time, the rubber band 49, with its projection 43 and its slot, is shielded by the wall of the waste spool 25, so that no yarn can come in contact with it. The ring rail then moves in a specified pattern of traverse motion, to produce the required type of package 37.

At the completion of winding, and whilst the machine is slowing down to rest, the ring 31 is lowered to the waste spool position that it was in at the start of the winding operation. This lowering of the ring, as shown in FIGURE 7, causes a wide-angled helix 51 of yarn to be wound, firstly over the lower portion of the package 37, next over the helical turns 45 on the lower portion of the bobbin 41 and then over those turns on the waste spool 25.

To dotf the bobbin (i.e. the bobbin 41 on which is wound yarn package 37) it is lifted upwardly along the spindle 23. This causes both the helical turns 45 and the wide-angled helical turns 51 to unwind somewhat and to slip where they are wound on the lower portion of the bobbin 41. The two spirals do, however, unwind in opposite directions. As shown in FIGURE 7, one turn of the spiral 45 becomes engaged with the outwardly-extending projection 43, enters the slot in the band 49 and is trapped therein. The turns of the wide-angled helix 51, unwinding in the opposite direction, slide over the projection 43 and do not enter the slot. The trapping of the yarn in the slot will be felt by the operative as he lifts the bobbin, and he knows that he can then cut the yarn in both spirals below the band 49. Thus, as shown in FIG- URE 8, the end 51 is free and the end 45 is trapped in the slot. Such trapping of the end 45 in this manner is quite secure enough for the ordinary incidents of handling; and no other means is required to secure the helical turns in place. These turns, comprising a transfer tail, are thus prepared on the ring spindle apparatus in the manner in which they are required for use in a subsequent textile operation such as warping.

What we claim is:

A process for winding yarn, and for dofling a yarn package so wound, on a ring spindle apparatus, comprising the steps of winding the initial lengths of yarn on a waste spool spaced heightwise below a bobbin, winding spaced turns of yarn in the form of a helix on the lower end-portion of said bobbin, said turns connecting the yarn on said waste spool with the main build of yarn on the bobbin, completing the winding of the main build of yarn, and doffing the bobbin by lifting it upwardly of the spindle of the said ring spindle apparatus so that yarn in the lower of said helical turns is automatically trapped in a slot formed by a radial projection from the surface of the bobbin, the line of direction of said slot towards its open end being such as to intersect the line of direction of yarn in said helical turns.

References Cited by the Examiner UNITED STATES PATENTS 2,747,359 5/1956 Keefe 57-345 2,932,149 4/ 1960 Ingham 5734 3,032,292 5/1962 Levinson 242-125.2

MERVIN STEIN, Primary Examiner.

D. E. WATKINS, Assistant Examiner. 

